Conventionally, in a traffic environment of a vehicle, a driving assistance device which assists a driver in driving operation of the vehicle is reported. For example, such driving assistance is conducted by notifying the driver of information about presence of a vehicle getting across a travel direction of an own vehicle.
Herein, the driving assistance when such vehicle turns right and the like at an intersection is desired to be sequentially and appropriately provided for the vehicle getting across a course of the own vehicle. Further, technology for providing the appropriate driving assistance according to a sequentially approaching oncoming vehicle is conventionally reported. For example, Patent Literature 1 discloses a right turn assistance information presenting device which displays a required distance to the oncoming vehicle estimated from time required for the right turn to be completed and a position of the oncoming vehicle before the right turn is started to the driver of the own vehicle when the own vehicle turns right at the intersection.
In addition, Patent Literature 2 discloses a method of presenting travel assistance information which does not carry out operation for avoiding collision when there is a predetermined number of or more approaching vehicles which travel on a lane intersecting with a travel lane of the own vehicle as conventional technology to carry out the driving assistance. Patent Literature 3 discloses a vehicular information providing device which, when there is a plurality of vehicles on an oncoming lane, calculates over taking possibility in a plurality of oncoming vehicles from a vehicle speed and a distance to the intersection.